Abstract

In the case of gate-valve cut-off, in very long transmission pipelines, considerable pressure overshoots are observed accompanying the gas flow impacts, caused as well by shock wave as by reflected one. The main factor, influencing the shock wave apmlitude, is the velocity of gate -valve closing, determined by the serwomotor-time-constant T_i. Because of possible variations of chemical constitution of gas transported through the pipeline - which renders physical, chamical and thermodynamic properties changes, it is necessary to examine theirs degree of influence on the processes of dynamic impact.